Thousands of years ago, a powerful undead entity, Ulvar, was captured by the followers of Kelemvor and sealed within a sanctum built specifically to contain it. The legendary archmage Ellan Mera — once a devoted priestess of Kelemvor and later his apostate — took on the role of the creature’s jailor. She was aided by many faithful servants, among them the renowned swordsman Yinsaren and a colossal golem of living sandstone.
Unfortunately, the creature’s power was greater than they had imagined. Over the millennia, it spread its corruption throughout the enclave. The waters turned white, saturated with necromantic energy, and a dreadful curse spread among the followers of Kelemvor. A thirst for blood grew within them, and those who succumbed to madness underwent a beastly transformation.
In the end, only Yinsaren and Ellan Mera survived — though both were broken by the curse. Only their shared purpose of keeping the creature imprisoned allowed them to restrain their insanity. Even the guardian golem became corrupted, its body bleeding as if it were flesh.
The Seekers eventually discovered the long-rumored enclave and, after facing many terrible creatures — including the corrupted golem (with Willow dying in battle against Yinsaren) — they confronted the corrupted Ellan Mera. As the Seekers fought the transformed archmage and her wounds deepened, the seals that kept the creature imprisoned broke, and it was freed.
Nothing the Seekers did could stop its escape. With Yinsaren in its grasp, the entity vanished from the ruins.